CompatHelper: bump compat for ArrayInterface to 4, (keep existing compat)

[github-actions]

This pull request changes the compat entry for the ArrayInterface package from 2, 3 to 2, 3, 4.
This keeps the compat entries for earlier versions.

Note: I have not tested your package with this new compat entry.
It is your responsibility to make sure that your package tests pass before you merge this pull request.

[codecov]

Codecov Report

Merging #25 (7b56569) into main (efc3cd8) will increase coverage by 0.17%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main      #25      +/-   ##
==========================================
+ Coverage   94.73%   94.91%   +0.17%     
==========================================
  Files           3        3              
  Lines          57       59       +2     
==========================================
+ Hits           54       56       +2     
  Misses          3        3              

Impacted Files	Coverage Δ
src/abstractmcmc.jl	100.00% <0.00%> (ø)
src/interface.jl	83.33% <0.00%> (+0.98%)	⬆️

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